Definition of High Mass in English:

noun

The Kyrie-Christe eleison, the Sanctus and the Agnus Dei are repeated three times in the course of a Low Mass and in addition, in the course of a High Mass, the censer is swung three times to waft incense over altar, servers and people.

I am almost certain that it is Anglican, but I was somewhat confused by the noticeboard outside advertising High Mass and Low Mass, and, inside the smell of incense.

Over the past seven days, more than 600 people came to hear Pope John Paul sing a High Mass.